During operation of work machines, it is sometimes desirable to move a work tool in a vibratory manner to accomplish some purpose. For example, an operator of an earth working machine having a work tool such as a bucket may desire to cause the bucket to move in a vibratory manner to (i) shake material out of the bucket that does not readily fall out, (ii) cause the bucket to penetrate hard material such as clay or rock, (iii) compact a surface, or (iv) perform some other function.
In the past, the standard method for vibrating a work tool has been for an operator to rapidly move the work tool control, such as a joystick or lever, back and forth until the task was completed. This method involves rapid motion by the operator that, over time, can become tedious and tiring. This technique is also only limited to certain work functions, such as shaking material out of the tool. Other functions, such as vibratory compaction of a surface, may not be efficiently performed by manual operation.
With the advent of electro-hydraulics, it has become possible to automate control of work tools in many ways that required manual control in the past. For example, computer-based controllers can be programmed to operate electro-hydraulic valves and solenoids with great precision, thus alleviating many of the difficult, tedious, tiring, or time-consuming tasks that operators previously had to perform.
In U.S. Pat. No. 5,860,231, Lee et al. discloses a system that automates the vibratory motion of a work tool by operator selection of a vibratory mode. The automatic method allows for work tool vibratory applications for several purposes, such as excavating, ground breaking, ground hardening (compaction), and the like.
Prior art devices and methods for controlling the vibratory motion of a work tool may still be improved by providing more sophisticated or more effective vibratory control mechanisms. For example, devices and methods may be desirable that effectively coordinate vibratory and non-vibratory operations among multiple work tool actuators.
The present invention is directed at overcoming one or more disadvantages associated with prior devices and methods for controlling vibratory operation of a work tool.